Islamic Militants Kill 56 Captive Syrian Soldiers

BEIRUT, Lebanon — Islamic militants led by an affiliate of Al Qaeda gunned down dozens of Syrian government soldiers taken prisoner during the takeover of a military air base this month, antigovernment activists said Saturday.

The execution of prisoners by all sides in the complex civil war has grown increasingly common as the conflict stretches into its fifth year.

At least 56 soldiers were killed by the Syrian affiliate of Al Qaeda, known as the Nusra Front, and its Islamist allies in recent days, according to the Syrian Observatory for Human Rights.

The soldiers were captured during the seizure of Abu Duhur Airbase in Idlib Province, the last military facility in the area to fall to the rebels.

The government of President Bashar al-Assad did not comment on the killings and said through state news media that all soldiers had been evacuated before the rebels arrived. The loss of the base and the executions are the latest blows to Mr. Assad, who has lost control of about three-quarters of the country.

A version of this article appears in print on , on Page A4 of the New York edition with the headline: Rebels Kill 56 Captive Syrian Soldiers . Order Reprints | Today’s Paper | Subscribe